Bicycle-chain outer link plate and bicycle chain

ABSTRACT

A bicycle-chain outer link plate comprises a first outer-link end portion, a second outer-link end portion, and a first outer-link intermediate portion. The first outer-link end portion comprises a first outer-link opening and a first outer-link end outermost edge. The second outer-link end portion comprises a second outer-link opening and a second outer-link end outermost edge. The first outer-link intermediate portion comprises a first outer-link intermediate outermost edge and a first additional outer-link intermediate outermost edge. The first outer-link intermediate portion has a first distance defined in an axial direction on a first outer-link longitudinal axis. The first outer-link intermediate outermost edge has a second distance defined in the axial direction. The first outer-link end outermost edge has a third distance defined in the axial direction. The first distance is larger than the second distance and the third distance. The second distance is larger than the third distance.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a bicycle-chain outer link plate and abicycle chain.

Discussion of the Background

Bicycling is becoming an increasingly more popular form of recreation aswell as a means of transportation. Moreover, bicycling has become a verypopular competitive sport for both amateurs and professionals. Whetherthe bicycle is used for recreation, transportation or competition, thebicycle industry is constantly improving the various components of thebicycle. One bicycle component that has been extensively redesigned is achain.

SUMMARY OF THE INVENTION

In accordance with a first aspect of the present invention, abicycle-chain outer link plate comprises a first outer-link end portion,a second outer-link end portion, and a first outer-link intermediateportion. The first outer-link end portion comprises a first outersurface, a first inner surface, a first outer-link opening, and a firstouter-link end outermost edge. The first inner surface is provided on areverse side of the first outer surface to face toward an additionalouter link plate in an assembled state where the bicycle-chain outerlink plate and the additional outer link plate are assembled. The firstouter-link opening has a first outer-link center axis and extending fromthe first outer surface to the first inner surface along the firstouter-link center axis. The first outer-link end outermost edge isprovided radially outwardly of the first outer-link opening. The secondouter-link end portion comprises a second outer surface, a second innersurface, a second outer-link opening, and a second outer-link endoutermost edge. The second inner surface is provided on a reverse sideof the second outer surface to face toward the additional outer linkplate in the assembled state. The second outer-link opening has a secondouter-link center axis and extends from the second outer surface to thesecond inner surface. The second outer-link end outermost edge isprovided radially outwardly of the second outer-link opening. The firstouter-link intermediate portion interconnects the first outer-link endportion and the second outer-link end portion. The first outer-linkintermediate portion comprises a first intermediate outer surface, afirst intermediate inner surface, a first outer-link intermediateoutermost edge, and a first additional outer-link intermediate outermostedge. The first intermediate inner surface is provided on a reverse sideof the first intermediate outer surface to face toward the additionalouter link plate in the assembled state. The first outer-linkintermediate outermost edge is provided between the first outer-link endoutermost edge and the second outer-link end outermost edge. The firstadditional outer-link intermediate outermost edge is provided betweenthe first outer-ling end outermost edge and the second outer-link endoutermost edge. The first outer-link intermediate portion has a firstdistance defined in an axial direction parallel to the first outer-linkcenter axis on a first outer-link longitudinal axis extending from thefirst outer-link center axis to the second outer-link center axis whenviewed in the axial direction. The first outer-link intermediateoutermost edge has a second distance defined in the axial direction. Thefirst outer-link end outermost edge has a third distance defined in theaxial direction. The first distance is larger than the second distanceand the third distance. The second distance is larger than the thirddistance.

With the bicycle-chain outer link plate according to the first aspect,it is possible to make a shifting operation smooth with reducing aneffect on strength of the bicycle-chain outer link plate in a case wherea width of the bicycle-chain outer link plate is reduced.

In accordance with a second aspect of the present invention, thebicycle-chain outer link plate according to the first aspect isconfigured so that the first distance ranges from 0.87 mm to 0.91 mm.

With the bicycle-chain outer link plate according to the second aspect,it is possible to make the shifting operation smoother with reducing aneffect on strength of the bicycle-chain outer link plate in a case wherea width of the bicycle-chain outer link plate is reduced.

In accordance with a third aspect of the present invention, thebicycle-chain outer link plate according to the first or second aspectis configured so that the second distance ranges from 0.79 mm to 0.83mm.

With the bicycle-chain outer link plate according to the third aspect,it is possible to make the shifting operation smoother with reducing aneffect on strength of the bicycle-chain outer link plate in a case wherea width of the bicycle-chain outer link plate is reduced.

In accordance with a fourth aspect of the present invention, thebicycle-chain outer link plate according to any one of the first tothird aspects is configured so that the third distance ranges from 0.44mm to 0.48 mm.

With the bicycle-chain outer link plate according to the fourth aspect,it is possible to make the shifting operation smoother with reducing aneffect on strength of the bicycle-chain outer link plate in a case wherea width of the bicycle-chain outer link plate is reduced.

In accordance with a fifth aspect of the present invention, abicycle-chain outer link plate comprises a first outer-link end portion,a second outer-link end portion, and a first outer-link intermediateportion. The first outer-link end portion comprises a first outersurface, a first inner surface, a first outer-link opening, and a firstouter-link end outermost edge. The first inner surface is provided on areverse side of the first outer surface to face toward an additionalouter link plate in an assembled state where the bicycle-chain outerlink plate and the additional outer link plate are assembled. The firstouter-link opening has a first outer-link center axis and extending fromthe first outer surface to the first inner surface along the firstouter-link center axis. The first outer-link end outermost edge isprovided radially outwardly of the first outer-link opening. The secondouter-link end portion comprises a second outer surface, a second innersurface, a second outer-link opening, and a second outer-link endoutermost edge. The second inner surface is provided on a reverse sideof the second outer surface to face toward the additional outer linkplate in the assembled state. The second outer-link opening has a secondouter-link center axis and extending from the second outer surface tothe second inner surface. The second outer-link end outermost edge isprovided radially outwardly of the second outer-link opening. The firstouter-link intermediate portion interconnects the first outer-link endportion and the second outer-link end portion. The first outer-linkintermediate portion comprises a first intermediate outer surface, afirst intermediate inner surface, a first outer-link intermediateoutermost edge, and a first additional outer-link intermediate outermostedge. The first intermediate inner surface is provided on a reverse sideof the first intermediate outer surface to face toward the additionalouter link plate in the assembled state. The first outer-linkintermediate outermost edge is provided between the first outer-ling endoutermost edge and the second outer-link end outermost edge. The firstadditional outer-link intermediate outermost edge is provided betweenthe first outer-ling end outermost edge and the second outer-link endoutermost edge. The first outer-link intermediate portion has a firstdistance defined in an axial direction parallel to the first outer-linkcenter axis on a first outer-link longitudinal axis extending from thefirst outer-link center axis to the second outer-link center axis whenviewed in the axial direction. The first outer-link intermediateoutermost edge has a second distance defined in the axial direction. Thesecond distance ranges from 89% to 93% of the first distance.

With the bicycle-chain outer link plate according to the fifth aspect,it is possible to make the shifting operation smooth with reducing aneffect on strength of the bicycle-chain outer link plate in a case wherea width of the bicycle-chain outer link plate is reduced.

In accordance with a sixth aspect of the present invention, thebicycle-chain outer link plate according to the fifth aspect isconfigured so that the first distance ranges from 0.87 mm to 0.91 mm.The second distance ranges from 0.79 mm to 0.83 mm.

With the bicycle-chain outer link plate according to the sixth aspect,it is possible to make the shifting operation smoother with reducing aneffect on strength of the bicycle-chain outer link plate in a case wherea width of the bicycle-chain outer link plate is reduced.

In accordance with a seventh aspect of the present invention, thebicycle-chain outer link plate according to any one of the first tosixth aspects is configured so that the first outer-link end portionincludes a first outer-link end chamfer and a first additionalouter-link end chamfer. The first outer-link end chamfer is provided onthe first outer surface. The first additional outer-link end chamfer isprovided on the first outer surface. The first outer-link end chamferextends along the first outer-link end outermost edge. The firstadditional outer-link end chamfer extends along the first outer-link endoutermost edge. The first additional outer-link end chamfer is providedbetween the first outer-link end outermost edge and the first outer-linkend chamfer.

With the bicycle-chain outer link plate according to the seventh aspect,it is possible to make the shifting operation smoother with reducing aneffect on strength of the bicycle-chain outer link plate in a case wherea width of the bicycle-chain outer link plate is reduced by changinggradually the width of the first outer-link end portion.

In accordance with an eighth aspect of the present invention, thebicycle-chain outer link plate according to the seventh aspect isconfigured so that the first outer-link end chamfer is adjacent to thefirst additional outer-link end chamfer without another chamfer betweenthe first outer-link end chamfer and the first additional outer-link endchamfer.

With the bicycle-chain outer link plate according to the eighth aspect,it is possible to make the shifting operation smoother with reducing aneffect on strength of the bicycle-chain outer link plate in a case wherea width of the bicycle-chain outer link plate is reduced by changinggradually the width of the first outer-link end portion.

In accordance with a ninth aspect of the present invention, thebicycle-chain outer link plate according to the seventh or eighth aspectis configured so that the first outer-link end chamfer includes a firstradially outer edge and a first radially inner edge. The firstadditional outer-link end chamfer includes a first additional radiallyouter edge and a first additional radially inner edge. The firstradially inner edge is coincident with the first additional radiallyouter edge.

With the bicycle-chain outer link plate according to the ninth aspect,it is possible to make the shifting operation smoother with reducing aneffect on strength of the bicycle-chain outer link plate in a case wherea width of the bicycle-chain outer link plate is reduced by changinggradually the width of the first outer-link end portion.

In accordance with a tenth aspect of the present invention, thebicycle-chain outer link plate according to the ninth aspect isconfigured so that the first outer-link end portion has a fourthdistance defined at the first radially outer edge of the firstouter-link end chamfer in the axial direction. The fourth distanceranges from 0.79 mm to 0.83 mm.

With the bicycle-chain outer link plate according to the tenth aspect,it is possible to make the shifting operation smoother with reducing aneffect on strength of the bicycle-chain outer link plate in a case wherea width of the bicycle-chain outer link plate is reduced by changinggradually the width of the first outer-link end portion.

In accordance with an eleventh aspect of the present invention, thebicycle-chain outer link plate according to the tenth aspect isconfigured so that the second distance corresponds to the fourthdistance.

With the bicycle-chain outer link plate according to the eleventhaspect, it is possible to make the shifting operation smoother withreducing an effect on strength of the bicycle-chain outer link plate ina case where a width of the bicycle-chain outer link plate is reduced bychanging gradually the width of the first outer-link end portion.

In accordance with a twelfth aspect of the present invention, thebicycle-chain outer link plate according to any one of the first toeleventh aspects further comprising an outline having an asymmetricshape relative to the first outer-link longitudinal axis when viewed inthe axial direction.

With the bicycle-chain outer link plate according to the twelfth aspect,the asymmetric shape can make the bicycle-chain outer link plate havedifferent functions on both sides.

In accordance with a thirteenth aspect of the present invention, thebicycle-chain outer link plate according to any one of the first totwelfth aspects is configured so that the second outer-link opening hasan elongated shape extending along the first outer-link longitudinalaxis.

With the bicycle-chain outer link plate according to the thirteenthaspect, it is possible to obtain the same effect as that of thebicycle-chain outer link plate according to the first aspect.

In accordance with a fourteenth aspect of the present invention, thebicycle-chain outer link plate according to the thirteenth aspect isconfigured so that the second outer-link opening has a longitudinalaxis. The longitudinal axis of the second outer-link opening is inclinedrelative to the first outer-link longitudinal axis when viewed in theaxial direction.

With the bicycle-chain outer link plate according to the fourteenthaspect, it is possible to improve a degree of freedom of designing ashape of the second outer-link opening.

In accordance with a fifteenth aspect of the present invention, abicycle chain comprises the bicycle-chain outer link plate according toany one of the first to fourteenth aspects and a first link pin. Thefirst link pin is provided in the first outer-link opening. The firstlink pin is engaged with the additional outer link plate.

With the bicycle chain according to the fifteenth aspect, thebicycle-chain outer link plate makes a shifting operation smooth withreducing an effect on strength of the bicycle-chain outer link plate ina case where a width of the bicycle-chain outer link plate is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings.

FIG. 1 is a side elevational view of a bicycle having a drive train thatuses a bicycle chain in accordance with an embodiment.

FIG. 2 is a partial plan view of the bicycle chain illustrated in FIG.1.

FIG. 3 is a partial perspective view of the bicycle chain illustrated inFIG. 1.

FIG. 4 is another partial perspective view of the bicycle chainillustrated in FIG. 1.

FIG. 5 is a side elevational view of a bicycle-chain outer link plate ofthe bicycle chain illustrated in FIG. 1.

FIG. 6 is a side elevational view of a bicycle-chain outer link plate inaccordance with a modification of the embodiment.

FIG. 7 is a cross-sectional view of the bicycle-chain outer link platetaken along line XII-XII of the FIG. 5.

FIG. 8 is a side elevational view of an additional outer link plate ofthe bicycle chain illustrated in FIG. 1.

FIG. 9 is a side elevational view of an additional outer link plate inaccordance with a modification of the embodiment.

FIG. 10 is a cross-sectional view of the additional outer link platetaken along line X-X of the FIG. 8.

FIG. 11 is a partial exploded perspective view of the bicycle chainillustrated in FIG. 1.

FIG. 12 is another partial exploded perspective view of the bicyclechain illustrated in FIG. 1.

FIG. 13 is a partial perspective cross-sectional view of thebicycle-chain outer link plate taken along line XIII-XIII of the FIG. 5.

FIG. 14 is another partial perspective cross-sectional view of thebicycle-chain outer link plate taken along line XIV-XIV of the FIG. 5.

FIG. 15 is a cross-sectional view of the bicycle-chain outer link platetaken along line XV-XV of the FIG. 5.

FIG. 16 is a partial perspective cross-sectional view of the additionalouter link plate taken along line XVI-XVI of the FIG. 8.

FIG. 17 is another partial perspective cross-sectional view of theadditional outer link plate taken along line XVII-XVII of the FIG. 8.

FIG. 18 is a partial perspective cross-sectional view of the additionalouter link plate taken along line XVIII-XVIII of the FIG. 8.

FIG. 19 is another side elevational view of the bicycle-chain outer linkplate illustrated in FIG. 5.

FIG. 20 is another side elevational view of a bicycle-chain outer linkplate in accordance with a modification of the embodiment.

FIG. 21 is another side elevational view of the additional outer linkplate illustrated in FIG. 8.

DESCRIPTION OF THE EMBODIMENTS

The embodiment(s) will now be described with reference to theaccompanying drawings, wherein like reference numerals designatecorresponding or identical elements throughout the various drawings.

Referring initially to FIG. 1, a bicycle 10 is illustrated to beequipped with a bicycle chain 12 in accordance with an embodiment. Thebicycle 10 includes a bicycle frame B1, a handlebar B2, a saddle B3, anda drive train B4. The drive train B4 is configured to convert therider's pedaling force into driving force. The bicycle chain 12 is apart of the drive train B4. The drive train B4 also includes a bicyclecrank assembly B5, a rear sprocket B6, a front derailleur B7, and a rearderailleur B8. The bicycle crank assembly B5 includes a front sprocketB51. The bicycle crank assembly B5 is rotatably mounted on a bottombracket of the bicycle frame B1 about a rotational center axis A1. Therear sprocket B6 is rotatably mounted to the bicycle frame B1 about arotational center axis A2. The bicycle chain 12 is arranged on the frontsprocket B51 and the rear sprocket B6 so as to extend therebetween. Thefront derailleur B7 and the rear derailleur B8 are configured andarranged to change gears by shifting the bicycle chain 12 in atransverse direction of the bicycle 10. The front sprocket B51 can alsobe referred to as a bicycle sprocket B51. The rear sprocket B6 can alsobe referred to as a bicycle sprocket B6.

In the present application, the following directional terms “front,”“rear,” “forward,” “rearward,” “left,” “right,” “transverse,” “upward”and “downward” as well as any other similar directional terms refer tothose directions which are determined on the basis of the rider who sitson the saddle B3 of the bicycle 10 with facing the handlebar B2, forexample. Accordingly, these terms, as utilized to describe the bicycle10 including the bicycle chain 12 should be interpreted relative to thebicycle 10 as used in an upright riding position on a horizontal surfaceas illustrated in FIG. 1. These terms, as utilized to describe thebicycle chain 12, should be interpreted relative to the bicycle chain 12as mounted on the bicycle 10 used in an upright riding position on ahorizontal surface as illustrated in FIG. 1.

As seen in FIG. 2, the bicycle chain 12 comprises a bicycle-chain outerlink plate 14 and a first link pin 16. The bicycle chain 12 comprises anadditional outer link plate 18, a second link pin 20, a first inner linkplate 22, and a second inner link plate 24, and a roller 28. Thebicycle-chain outer link plate 14 is spaced apart from the additionalouter link plate 18. The first inner link plate 22 and the second innerlink plate 24 are provided between the bicycle-chain outer link plate 14and the additional outer link plate 18. The roller 28 is providedbetween the first inner link plate 22 and the second inner link plate24. The bicycle chain 12 has a driving direction DD in which the bicyclechain 12 transmits a pedaling force F1 during pedaling. Thebicycle-chain outer link plate 14 can also be referred to as a firstouter link plate 14. The additional outer link plate 18 can also bereferred to as a second outer link plate 18.

In this embodiment, the bicycle-chain outer link plate 14 and theadditional outer link plate 18 are connector link plates to connect oneend of a chain to the other end of the chain. Thus, the bicycle-chainouter link plate 14 can also be referred to as a first connector linkplate 14. The additional outer link plate 18 can also be referred to asa second connector link plate 18. However, the bicycle-chain outer linkplate 14 and the additional outer link plate 18 are not limited to aconnector link plate. The bicycle-chain outer link plate 14 and theadditional outer link plate 18 can be an outer link plate.

As seen in FIGS. 3 and 4, the bicycle-chain outer link plate 14comprises a first outer-link end portion 30, a second outer-link endportion 32, and a first outer-link intermediate portion 34. The firstouter-link intermediate portion 34 interconnects the first outer-linkend portion 30 and the second outer-link end portion 32. The firstouter-link intermediate portion 34 is provided between the firstouter-link end portion 30 and the second outer-link end portion 32.

As seen in FIG. 2, the first outer-link end portion 30 comprises a firstouter surface 30A and a first inner surface 30B. The first inner surface30B is provided on a reverse side of the first outer surface 30A to facetoward the additional outer link plate 18 in an assembled state wherethe bicycle-chain outer link plate 14 and the additional outer linkplate 18 are assembled. The second outer-link end portion 32 comprises asecond outer surface 32A and a second inner surface 32B. The secondinner surface 32B is provided on a reverse side of the second outersurface 32A to face toward the additional outer link plate 18 in theassembled state. The first outer-link intermediate portion 34 comprisesa first intermediate outer surface 34A and a first intermediate innersurface 34B. The first intermediate inner surface 34B is provided on areverse side of the first intermediate outer surface 34A to face towardthe additional outer link plate 18 in the assembled state.

As seen in FIG. 5, the first outer-link end portion 30 comprises a firstouter-link opening 30C having a first outer-link center axis CAW Thefirst outer-link end portion 30 comprises a first outer-link endoutermost edge 30E provided radially outwardly of the first outer-linkopening 30C. The second outer-link end portion 32 comprises a secondouter-link opening 32C having a second outer-link center axis CA12. Thesecond outer-link end portion 32 comprises a second outer-link endoutermost edge 32E provided radially outwardly of the second outer-linkopening 32C. The first outer-link intermediate portion 34 comprises afirst outer-link intermediate outermost edge 34E and a first additionalouter-link intermediate outermost edge 34F. The first outer-linkintermediate outermost edge 34E is provided between the first outer-linkend outermost edge 30E and the second outer-link end outermost edge 32E.The first additional outer-link intermediate outermost edge 34F isprovided between the first outer-link end outermost edge 30E and thesecond outer-link end outermost edge 32E.

The bicycle-chain outer link plate 14 comprises a first outer-linklongitudinal axis LA11 extending from the first outer-link center axisCA11 to the second outer-link center axis CA12 when viewed in the axialdirection D1 (FIG. 2) parallel to the first outer-link center axis CA11.The bicycle-chain outer link plate 14 further comprises an outlinehaving an asymmetric shape relative to the first outer-link longitudinalaxis LA11 when viewed in the axial direction D1 (FIG. 2). However, theoutline of the bicycle-chain outer link plate 14 can have a symmetricshape relative to the first outer-link longitudinal axis LA11 whenviewed in the axial direction D1.

In this embodiment, the first outer-link opening 30C has a circularshape. The second outer-link opening 32C has an elongated shapeextending along the first outer-link longitudinal axis LA11. The secondouter-link opening 32C has a longitudinal axis LA12. The longitudinalaxis LA12 of the second outer-link opening 32C is inclined relative tothe first outer-link longitudinal axis LA11 when viewed in the axialdirection D1. As seen in FIG. 6, however, the longitudinal axis LA12 ofthe second outer-link opening 32C can be parallel to the firstouter-link longitudinal axis LA11 when viewed in the axial direction D1.

As seen in FIG. 5, the second outer-link opening 32C includes anattachment opening 32C1 and an insertion opening 32C2. The attachmentopening 32C1 is connected to the insertion opening 32C2. The attachmentopening 32C1 has an attachment center axis CA13. The insertion opening32C2 has an insertion center axis CA14. The longitudinal axis LA12 ofthe second outer-link opening 32C extends from the attachment centeraxis CA13 to the insertion center axis CA14 when viewed in the axialdirection D1 (FIG. 2). In this embodiment, the second outer-link centeraxis CA12 is coincident with the attachment center axis CA13. However,the second outer-link center axis CA12 can be offset from the attachmentcenter axis CA13.

As seen in FIG. 7, the first outer-link opening 30C extends from thefirst outer surface 30A to the first inner surface 30B along the firstouter-link center axis CA11. The second outer-link opening 32C extendsfrom the second outer surface 32A to the second inner surface 32B.

As seen in FIGS. 3 and 4, the additional outer link plate 18 comprises athird outer-link end portion 40, a fourth outer-link end portion 42, anda second outer-link intermediate portion 44. The second outer-linkintermediate portion 44 interconnects the third outer-link end portion40 and the fourth outer-link end portion 42. The second outer-linkintermediate portion 44 is provided between the third outer-link endportion 40 and the fourth outer-link end portion 42.

As seen in FIG. 2, the third outer-link end portion 40 comprises a thirdouter surface 40A and a third inner surface 40B. The third inner surface40B is provided on a reverse side of the third outer surface 40A to facetoward the additional outer link plate 18 in the assembled state wherethe bicycle-chain outer link plate 14 and the additional outer linkplate 18 are assembled. The fourth outer-link end portion 42 comprises afourth outer surface 42A and a fourth inner surface 42B. The fourthinner surface 42B is provided on a reverse side of the fourth outersurface 42A to face toward the additional outer link plate 18 in theassembled state. The second outer-link intermediate portion 44 comprisesa second intermediate outer surface 44A and a second intermediate innersurface 44B. The second intermediate inner surface 44B is provided on areverse side of the second intermediate outer surface 44A to face towardthe additional outer link plate 18 in the assembled state.

As seen in FIG. 8, the third outer-link end portion 40 comprises a thirdouter-link opening 40C having a third outer-link center axis CA21. Thethird outer-link end portion 40 comprises a third outer-link endoutermost edge 40E provided radially outwardly of the third outer-linkopening 40C. The fourth outer-link end portion 42 comprises a fourthouter-link opening 42C having a fourth outer-link center axis CA22. Thefourth outer-link end portion 42 comprises a fourth outer-link endoutermost edge 42E provided radially outwardly of the fourth outer-linkopening 42C. The second outer-link intermediate portion 44 comprises asecond outer-link intermediate outermost edge 44E and a secondadditional outer-link intermediate outermost edge 44F. The secondouter-link intermediate outermost edge 44E is provided between the thirdouter-link end outermost edge 40E and the fourth outer-link endoutermost edge 42E. The second additional outer-link intermediateoutermost edge 44F is provided between the third outer-link endoutermost edge 40E and the fourth outer-link end outermost edge 42E.

The additional outer link plate 18 comprises a second outer-linklongitudinal axis LA21 extending from the third outer-link center axisCA21 to the fourth outer-link center axis CA22 when viewed in the axialdirection D1. The additional outer link plate 18 further comprises anoutline having an asymmetric shape relative to the second outer-linklongitudinal axis LA21 when viewed in the axial direction D1. However,the outline of the additional outer link plate 18 can have a symmetricshape relative to the second outer-link longitudinal axis LA21 whenviewed in the axial direction D1.

In this embodiment, the third outer-link opening 40C has a circularshape. The fourth outer-link opening 42C has an elongated shapeextending along the second outer-link longitudinal axis LA21. The fourthouter-link opening 42C has a longitudinal axis LA22. The longitudinalaxis LA22 of the fourth outer-link opening 42C is inclined relative tothe second outer-link longitudinal axis LA21 when viewed in the axialdirection D1. As seen in FIG. 9, however, the longitudinal axis LA22 ofthe fourth outer-link opening 42C can be parallel to the secondouter-link longitudinal axis LA21 when viewed in the axial direction D1.

As seen in FIG. 8, the fourth outer-link opening 42C includes anattachment opening 42C1 and an insertion opening 42C2. The attachmentopening 42C1 is connected to the insertion opening 42C2. The attachmentopening 42C1 has an attachment center axis CA23. The insertion opening42C2 has an insertion center axis CA14. The longitudinal axis LA22 ofthe fourth outer-link opening 42C extends from the attachment centeraxis CA23 to the insertion center axis CA14. In this embodiment, thefourth outer-link center axis CA22 is coincident with the attachmentcenter axis CA23. However, the fourth outer-link center axis CA22 can beoffset from the attachment center axis CA23.

As seen in FIG. 10, the third outer-link opening 40C extends from thethird outer surface 40A to the third inner surface 40B along the thirdouter-link center axis CA21. The fourth outer-link opening 42C extendsfrom the fourth outer surface 42A to the fourth inner surface 42B.

As seen in FIG. 3, the first link pin 16 is provided in the firstouter-link opening 30C. The first link pin 16 is engaged with theadditional outer link plate 18. The second link pin 20 is provided inthe second outer-link opening 32C. The second link pin 20 is engagedwith the additional outer link plate 18. As seen in FIG. 4, the firstlink pin 16 is provided in the fourth outer-link opening 42C. The secondlink pin 20 is provided in the third outer-link opening 40C.

As seen in FIG. 2, the first inner link plate 22 and the second innerlink plate 24 are pivotally coupled to the bicycle-chain outer linkplate 14 and the additional outer link plate 18 with the first link pin16. The first inner link plate 22 and the second inner link plate 24 arepivotally coupled to the bicycle-chain outer link plate 14 and theadditional outer link plate 18 with the second link pin 20.

As seen in FIG. 11, the first link pin 16 includes a first pin body 16A,a first head part 16B, a first intermediate part 16C, and a first groove16D. The first pin body 16A is provided in the first outer-link opening30C. In this embodiment, for example, the first pin body 16A ispress-fitted in the first outer-link opening 30C. The first intermediatepart 16C couples the first head part 16B to the first pin body 16A. Thefirst groove 16D is provided between the first pin body 16A and thefirst head part 16B. The first intermediate part 16C is provided in thefourth outer-link opening 42C.

As seen in FIG. 12, the additional outer link plate 18 includes a guidepart 42K provided in the fourth outer-link opening 42C. The guide part42K extends from an inner peripheral surface of the fourth outer-linkopening 42C. As seen in FIG. 4, the guide part 42K is provided in thefirst groove 16D of the first link pin 16 in the assembled state.

As seen in FIG. 12, the second link pin 20 includes a second pin body20A, a second head part 20B, a second intermediate part 20C, and asecond groove 20D. The second pin body 20A is provided in the thirdouter-link opening 40C. In this embodiment, for example, the second pinbody 20A is press-fitted in the third outer-link opening 40C. The secondintermediate part 20C couples the second head part 20B to the second pinbody 20A. The second groove 20D is provided between the second pin body20A and the second head part 20B. The second intermediate part 20C isprovided in the second opening.

As seen in FIG. 11, the bicycle-chain outer link plate 14 includes aguide part 32K provided in the second outer-link opening 32C. The guidepart 32K extends from an inner peripheral surface of the secondouter-link opening 32C. As seen in FIG. 3, the guide part 32K isprovided in the second groove 20D of the second link pin 20 in theassembled state.

As seen in FIG. 5, the first outer-link end portion 30 includes a firstouter-link end chamfer 30F and a first additional outer-link end chamfer30G. The first outer-link end chamfer 30F is provided on the first outersurface 30A. The first additional outer-link end chamfer 30G is providedon the first outer surface 30A. The first outer-link end chamfer 30Fextends along the first outer-link end outermost edge 30E. The firstadditional outer-link end chamfer 30G extends along the first outer-linkend outermost edge 30E. The first additional outer-link end chamfer 30Gis provided between the first outer-link end outermost edge 30E and thefirst outer-link end chamfer 30F. In this embodiment, the firstouter-link end chamfer 30F is adjacent to the first additionalouter-link end chamfer 30G without another chamfer between the firstouter-link end chamfer 30F and the first additional outer-link endchamfer 30G. However, another chamfer can be provided between the firstouter-link end chamfer 30F and the first additional outer-link endchamfer 30G.

As seen in FIG. 13, the first outer-link end chamfer 30F includes afirst radially outer edge 30F1 and a first radially inner edge 30F2. Thefirst additional outer-link end chamfer 30G includes a first additionalradially outer edge 30G1 and a first additional radially inner edge30G2. The first radially inner edge 30F2 is coincident with the firstadditional radially outer edge 30G1. However, the first radially inneredge 30F2 can be offset from the first additional radially outer edge30G1.

As seen in FIG. 5, the second outer-link end portion 32 includes asecond outer-link end chamfer 32F and a second additional outer-link endchamfer 32G. The second outer-link end chamfer 32F is provided on thesecond outer surface 32A. The second additional outer-link end chamfer32G is provided on the second outer surface 32A. The second outer-linkend chamfer 32F extends along the second outer-link end outermost edge32E. The second additional outer-link end chamfer 32G extends along thesecond outer-link end outermost edge 32E. The second additionalouter-link end chamfer 32G is provided between the second outer-link endoutermost edge 32E and the second outer-link end chamfer 32F. In thisembodiment, the second outer-link end chamfer 32F is adjacent to thesecond additional outer-link end chamfer 32G without another chamferbetween the second outer-link end chamfer 32F and the second additionalouter-link end chamfer 32G. However, another chamfer can be providedbetween the second outer-link end chamfer 32F and the second additionalouter-link end chamfer 32G.

As seen in FIG. 14, the second outer-link end chamfer 32F includes asecond radially outer edge 32F1 and a second radially inner edge 32F2.The second additional outer-link end chamfer 32G includes a secondadditional radially outer edge 32G1 and a second additional radiallyinner edge 32G2. The second radially inner edge 32F2 is coincident withthe second additional radially outer edge 32G1. However, the secondradially inner edge 32F2 can be offset from the second additionalradially outer edge 32G1.

As seen in FIG. 15, the first outer-link intermediate portion 34 has afirst distance T11 defined in an axial direction D1 parallel to thefirst outer-link center axis CA11 on the first outer-link longitudinalaxis LA11. The first outer-link intermediate outermost edge 34E has asecond distance T12 defined in the axial direction D1. The firstouter-link end outermost edge 30E has a third distance T13 defined inthe axial direction D1. The first distance T11 is larger than the seconddistance T12 and the third distance T13. The second distance T12 islarger than the third distance T13. In this embodiment, each of thefirst distance T11, the second distance T12, the third distance T13, andthe fourth distance T14 is defined from the first intermediate innersurface 34B in the axial direction D1.

In this embodiment, the first distance T11 ranges from 0.87 mm to 0.91mm. The second distance T12 ranges from 0.79 mm to 0.83 mm. The thirddistance T13 ranges from 0.44 mm to 0.48 mm. In this embodiment, thefirst distance T11 is 0.89 mm. The second distance T12 is 0.81 mm. Thethird distance T13 is 0.46 mm. However, each of the first distance T11,the second distance T12, and the third distance T13 is not limited tothis embodiment and the above ranges. The second distance T12 rangesfrom 89% to 93% of the first distance T11. In this embodiment, thesecond distance T12 is approximately 91% of the first distance T11.However, a ratio of the second distance T12 to the first distance T11 isnot limited to this embodiment.

The first outer-link end portion 30 has a fourth distance T14 defined atthe first radially outer edge 30F1 of the first outer-link end chamfer30F in the axial direction D1. The fourth distance T14 ranges from 0.79mm to 0.83 mm. In this embodiment, the fourth distance T14 is 0.81 mm.Namely, the second distance T12 corresponds to the fourth distance T14.The second distance T12 is equal to the fourth distance T14. However,the fourth distance T14 is not limited to this embodiment and the aboveranges. The fourth distance T14 can be different from the seconddistance T12.

As seen in FIG. 8, the third outer-link end portion 40 includes a thirdouter-link end chamfer 40F and a third additional outer-link end chamfer40G. The third outer-link end chamfer 40F is provided on the third outersurface 40A. The third additional outer-link end chamfer 40G is providedon the third outer surface 40A. The third outer-link end chamfer 40Fextends along the third outer-link end outermost edge 40E. The thirdadditional outer-link end chamfer 40G extends along the third outer-linkend outermost edge 40E. The third additional outer-link end chamfer 40Gis provided between the third outer-link end outermost edge 40E and thethird outer-link end chamfer 40F. In this embodiment, the thirdouter-link end chamfer 40F is adjacent to the third additionalouter-link end chamfer 40G without another chamfer between the thirdouter-link end chamfer 40F and the third additional outer-link endchamfer 40G. However, another chamfer can be provided between the thirdouter-link end chamfer 40F and the third additional outer-link endchamfer 40G.

As seen in FIG. 16, the third outer-link end chamfer 40F includes athird radially outer edge 40F1 and a third radially inner edge 40F2. Thethird additional outer-link end chamfer 40G includes a third additionalradially outer edge 40G1 and a third additional radially inner edge40G2. The third radially inner edge 40F2 is coincident with the thirdadditional radially outer edge 40G1. However, the third radially inneredge 40F2 can be offset from the third additional radially outer edge40G1.

As seen in FIG. 8, the fourth outer-link end portion 42 includes afourth outer-link end chamfer 42F and a fourth additional outer-link endchamfer 42G. The fourth outer-link end chamfer 42F is provided on thefourth outer surface 42A. The fourth additional outer-link end chamfer42G is provided on the fourth outer surface 42A. The fourth outer-linkend chamfer 42F extends along the fourth outer-link end outermost edge42E. The fourth additional outer-link end chamfer 42G extends along thefourth outer-link end outermost edge 42E. The fourth additionalouter-link end chamfer 42G is provided between the fourth outer-link endoutermost edge 42E and the fourth outer-link end chamfer 42F. In thisembodiment, the fourth outer-link end chamfer 42F is adjacent to thefourth additional outer-link end chamfer 42G without another chamferbetween the fourth outer-link end chamfer 42F and the fourth additionalouter-link end chamfer 42G. However, another chamfer can be providedbetween the fourth outer-link end chamfer 42F and the fourth additionalouter-link end chamfer 42G.

As seen in FIG. 17, the fourth outer-link end chamfer 42F includes afourth radially outer edge 42F1 and a fourth radially inner edge 42F2.The fourth additional outer-link end chamfer 42G includes a fourthadditional radially outer edge 42G1 and a fourth additional radiallyinner edge 42G2. The fourth radially inner edge 42F2 is coincident withthe fourth additional radially outer edge 42G1. However, the fourthradially inner edge 42F2 can be offset from the fourth additionalradially outer edge 42G1.

As seen in FIG. 18, the second outer-link intermediate portion 44 has afirst distance T21 defined in the axial direction D1 parallel to thethird outer-link center axis CA21 on the second outer-link longitudinalaxis LA21. The second outer-link intermediate outermost edge 44E has asecond distance T22 defined in the axial direction D1. The thirdouter-link end outermost edge 40E has a third distance T23 defined inthe axial direction D1. The first distance T21 is larger than the seconddistance T22 and the third distance T23. The second distance T22 islarger than the third distance T23. In this embodiment, each of thefirst distance T21, the second distance T22, the third distance T23, andthe fourth distance T24 is defined from the second intermediate innersurface 44B in the axial direction D1.

In this embodiment, the first distance T21 ranges from 0.87 mm to 0.91mm. The second distance T22 ranges from 0.79 mm to 0.83 mm. The thirddistance T23 ranges from 0.44 mm to 0.48 mm. In this embodiment, thefirst distance T21 is 0.89 mm. The second distance T22 is 0.81 mm. Thethird distance T23 is 0.46 mm. However, each of the first distance T21,the second distance T22, and the third distance T23 is not limited tothis embodiment and the above ranges. The second distance T22 rangesfrom 89% to 93% of the first distance T21. In this embodiment, thesecond distance T22 is approximately 91% of the first distance T21.However, a ratio of the second distance T22 to the first distance T21 isnot limited to this embodiment.

The third outer-link end portion 40 has a fourth distance T24 defined atthe third radially outer edge 40F1 of the third outer-link end chamfer40F in the axial direction D1. The fourth distance T24 ranges from 0.79mm to 0.83 mm. In this embodiment, the fourth distance T24 is 0.81 mm.Namely, the second distance T22 corresponds to the fourth distance T24.The second distance T22 is equal to the fourth distance T24. However,the fourth distance T24 is not limited to this embodiment and the aboveranges. The fourth distance T24 can be different from the seconddistance T22.

As seen in FIG. 19, the first outer-link intermediate portion 34comprises a first intermediate chamfer 34G extending along the firstouter-link intermediate outermost edge 34E. The first intermediatechamfer 34G has a first inner edge 34G1. The first intermediate chamfer34G is provided between the first outer-link intermediate outermost edge34E and the first inner edge 34G1. The first intermediate chamfer 34Gextends from the first outer-link intermediate outermost edge 34E towardthe first additional outer-link intermediate outermost edge 34F. Thefirst intermediate chamfer 34G is provided on the first intermediateinner surface 34B and is disposed between the first outer-link endportion 30 and the second outer-link end portion 32.

The first intermediate chamfer 34G has a first minimum distance MD11defined between the first outer-link intermediate outermost edge 34E andthe first inner edge 34G1 along a reference line RL1. The reference lineRL1 is perpendicular to a first outer-link longitudinal axis LA11. Thefirst outer-link longitudinal axis LA11 extends from the firstouter-link center axis CA11 to the second outer-link center axis CA12when viewed in the axial direction D1 parallel to the first outer-linkcenter axis CA11. A distance DS1 defined between the first outer-linkintermediate outermost edge 34E and the first additional outer-linkintermediate outermost edge 34F on the reference line RL1 is minimum inthe first outer-link intermediate portion 34. The reference line RL1extends from a center of curvature CC1 of a reference circular arc RC1corresponding to the first outer-link intermediate outermost edge 34Ewhen viewed in the axial direction D1. The first minimum distance MD11is equal to or larger than 1 mm. The first minimum distance MD11 isequal to or smaller than 2 mm. In this embodiment, the first minimumdistance MD11 is 1.5 mm. However, the first minimum distance MD11 is notlimited to this embodiment and the above ranges.

The first outer-link intermediate portion 34 includes a first additionalintermediate chamfer 34H extending along the first additional outer-linkintermediate outermost edge 34F. The first additional intermediatechamfer 34H has a first additional inner edge 34H1. The first additionalintermediate chamfer 34H is provided between the first additionalouter-link intermediate outermost edge 34F and the first additionalinner edge 34H1. The first additional intermediate chamfer 34H extendsfrom the first additional outer-link intermediate outermost edge 34Ftoward the first outer-link intermediate outermost edge 34E. The firstadditional intermediate chamfer 34H is provided on the firstintermediate inner surface 34B and is disposed between the firstouter-link end portion 30 and the second outer-link end portion 32.

The first additional intermediate chamfer 34H has a first additionalminimum distance MD12 defined between the first additional outer-linkintermediate outermost edge 34F and the first additional radially inneredge 30G2 along the reference line RL1. The first additional minimumdistance MD12 is equal to or larger than 1 mm. The first additionalminimum distance MD12 is equal to or smaller than 2 mm. In thisembodiment, the first additional minimum distance MD12 is 1.5 mm.Namely, the first additional minimum distance MD12 is equal to the firstminimum distance MD11. As seen in FIG. 20, however, the first additionalminimum distance MD12 can be different from the first minimum distanceMD11. As seen in FIG. 17, however, the first additional minimum distanceMD12 can be different from the first minimum distance MD11.

As seen in FIG. 21, the second outer-link intermediate portion 44comprises a second intermediate chamfer 44G extending along the secondouter-link intermediate outermost edge 44E. The second intermediatechamfer 44G has a second inner edge 44G1. The second intermediatechamfer 44G is provided between the second outer-link intermediateoutermost edge 44E and the second inner edge 44G1. The secondintermediate chamfer 44G extends from the second outer-link intermediateoutermost edge 44E toward the second additional outer-link intermediateoutermost edge 44F. The second intermediate chamfer 44G is provided onthe second intermediate inner surface 44B and is disposed between thethird outer-link end portion 40 and the fourth outer-link end portion42.

The second intermediate chamfer 44G has a second minimum distance MD21defined between the second outer-link intermediate outermost edge 44Eand the second inner edge 44G1 along a reference line RL2. The referenceline RL2 is perpendicular to a first outer-link longitudinal axis LA11.The first outer-link longitudinal axis LA11 extends from the thirdouter-link center axis CA21 to the fourth outer-link center axis CA22when viewed in the axial direction D1 parallel to the third outer-linkcenter axis CA21. A distance DS1 defined between the second outer-linkintermediate outermost edge 44E and the second additional outer-linkintermediate outermost edge 44F on the reference line RL2 is minimum inthe second outer-link intermediate portion 44. The reference line RL2extends from a center of curvature CC2 of a reference circular arc RC2corresponding to the second outer-link intermediate outermost edge 44Ewhen viewed in the axial direction D1. The second minimum distance MD21is equal to or larger than 1 mm. The second minimum distance MD21 isequal to or smaller than 2 mm. In this embodiment, the second minimumdistance MD21 is 1.5 mm. However, the second minimum distance MD21 isnot limited to this embodiment and the above ranges.

The second outer-link intermediate portion 44 includes a secondadditional intermediate chamfer 44H extending along the secondadditional outer-link intermediate outermost edge 44F. The secondadditional intermediate chamfer 44H has a second additional inner edge44H1. The second additional intermediate chamfer 44H is provided betweenthe second additional outer-link intermediate outermost edge 44F and thesecond additional inner edge 44H1. The second additional intermediatechamfer 44H extends from the second additional outer-link intermediateoutermost edge 44F toward the second outer-link intermediate outermostedge 44E. The second additional intermediate chamfer 44H is provided onthe second intermediate inner surface 44B and is disposed between thethird outer-link end portion 40 and the fourth outer-link end portion42.

The second additional intermediate chamfer 44H has a second additionalminimum distance MD22 defined between the second additional outer-linkintermediate outermost edge 44F and the third additional radially inneredge 40G2 along the reference line RL2. The second additional minimumdistance MD22 is equal to or larger than 1 mm. The second additionalminimum distance MD22 is equal to or smaller than 2 mm. In thisembodiment, the second additional minimum distance MD22 is 1.5 mm.Namely, the second additional minimum distance MD22 is equal to thesecond minimum distance MD21. Similarly to the bicycle-chain outer linkplate 14 illustrated in FIG. 20, however, the second additional minimumdistance MD22 can be different from the second minimum distance MD21.

The term “comprising” and its derivatives, as used herein, are intendedto be open ended terms that specify the presence of the stated features,elements, components, groups, integers, and/or steps, but do not excludethe presence of other unstated features, elements, components, groups,integers and/or steps. This concept also applies to words of similarmeaning, for example, the terms “have,” “include” and their derivatives.

The terms “member,” “section,” “portion,” “part,” “element,” “body” and“structure” when used in the singular can have the dual meaning of asingle part or a plurality of parts.

The ordinal numbers such as “first” and “second” recited in the presentapplication are merely identifiers, but do not have any other meanings,for example, a particular order and the like. Moreover, for example, theterm “first element” itself does not imply an existence of “secondelement,” and the term “second element” itself does not imply anexistence of “first element.”

The term “pair of,” as used herein, can encompass the configuration inwhich the pair of elements have different shapes or structures from eachother in addition to the configuration in which the pair of elementshave the same shapes or structures as each other.

The terms “a” (or “an”), “one or more” and “at least one” can be usedinterchangeably herein.

Finally, terms of degree such as “substantially,” “about” and“approximately” as used herein mean a reasonable amount of deviation ofthe modified term such that the end result is not significantly changed.All of numerical values described in the present application can beconstrued as including the terms such as “substantially,” “about” and“approximately.”

Obviously, numerous modifications and variations of the presentinvention are possible in light of the above teachings. It is thereforeto be understood that within the scope of the appended claims, theinvention may be practiced otherwise than as specifically describedherein.

What is claimed is:
 1. A bicycle-chain outer link plate comprising: afirst outer-link end portion comprising: a first outer surface; a firstinner surface provided on a reverse side of the first outer surface toface toward an additional outer link plate in an assembled state wherethe bicycle-chain outer link plate and the additional outer link plateare assembled; a first outer-link opening having a first outer-linkcenter axis and extending from the first outer surface to the firstinner surface along the first outer-link center axis; and a firstouter-link end outermost edge provided radially outwardly of the firstouter-link opening; a second outer-link end portion comprising: a secondouter surface; a second inner surface provided on a reverse side of thesecond outer surface to face toward the additional outer link plate inthe assembled state; a second outer-link opening having a secondouter-link center axis and extending from the second outer surface tothe second inner surface; and a second outer-link end outermost edgeprovided radially outwardly of the second outer-link opening; and afirst outer-link intermediate portion interconnecting the firstouter-link end portion and the second outer-link end portion, the firstouter-link intermediate portion comprising: a first intermediate outersurface; a first intermediate inner surface provided on a reverse sideof the first intermediate outer surface to face toward the additionalouter link plate in the assembled state; a first outer-link intermediateoutermost edge provided between the first outer-link end outermost edgeand the second outer-link end outermost edge; and a first additionalouter-link intermediate outermost edge provided between the firstouter-ling end outermost edge and the second outer-link end outermostedge, the first outer-link intermediate portion having a first distancedefined in an axial direction parallel to the first outer-link centeraxis on a first outer-link longitudinal axis extending from the firstouter-link center axis to the second outer-link center axis when viewedin the axial direction, the first outer-link intermediate outermost edgehaving a second distance defined in the axial direction, and the firstouter-link end outermost edge having a third distance defined in theaxial direction, the first distance being larger than the seconddistance and the third distance, the second distance being larger thanthe third distance.
 2. The bicycle-chain outer link plate according toclaim 1, wherein the first distance ranges from 0.87 mm to 0.91 mm. 3.The bicycle-chain outer link plate according to claim 1, wherein thesecond distance ranges from 0.79 mm to 0.83 mm.
 4. The bicycle-chainouter link plate according to claim 1, wherein the third distance rangesfrom 0.44 mm to 0.48 mm.
 5. A bicycle-chain outer link plate comprising:a first outer-link end portion comprising: a first outer surface; afirst inner surface provided on a reverse side of the first outersurface to face toward an additional outer link plate in an assembledstate where the bicycle-chain outer link plate and the additional outerlink plate are assembled; a first outer-link opening having a firstouter-link center axis and extending from the first outer surface to thefirst inner surface along the first outer-link center axis; and a firstouter-link end outermost edge provided radially outwardly of the firstouter-link opening; a second outer-link end portion comprising: a secondouter surface; a second inner surface provided on a reverse side of thesecond outer surface to face toward the additional outer link plate inthe assembled state; a second outer-link opening having a secondouter-link center axis and extending from the second outer surface tothe second inner surface; and a second outer-link end outermost edgeprovided radially outwardly of the second outer-link opening; and afirst outer-link intermediate portion interconnecting the firstouter-link end portion and the second outer-link end portion, the firstouter-link intermediate portion comprising: a first intermediate outersurface; a first intermediate inner surface provided on a reverse sideof the first intermediate outer surface to face toward the additionalouter link plate in the assembled state; a first outer-link intermediateoutermost edge provided between the first outer-link end outermost edgeand the second outer-link end outermost edge; and a first additionalouter-link intermediate outermost edge provided between the firstouter-ling end outermost edge and the second outer-link end outermostedge, the first outer-link intermediate portion having a first distancedefined in an axial direction parallel to the first outer-link centeraxis on a first outer-link longitudinal axis extending from the firstouter-link center axis to the second outer-link center axis when viewedin the axial direction, the first outer-link intermediate outermost edgehaving a second distance defined in the axial direction, and the seconddistance ranging from 89% to 93% of the first distance.
 6. Thebicycle-chain outer link plate according to claim 5, wherein the firstdistance ranges from 0.87 mm to 0.91 mm, and the second distance rangesfrom 0.79 mm to 0.83 mm.
 7. The bicycle-chain outer link plate accordingto claim 1, wherein the first outer-link end portion includes a firstouter-link end chamfer provided on the first outer surface, and a firstadditional outer-link end chamfer provided on the first outer surface,the first outer-link end chamfer extends along the first outer-link endoutermost edge, the first additional outer-link end chamfer extendsalong the first outer-link end outermost edge, and the first additionalouter-link end chamfer is provided between the first outer-link endoutermost edge and the first outer-link end chamfer.
 8. Thebicycle-chain outer link plate according to claim 7, wherein the firstouter-link end chamfer is adjacent to the first additional outer-linkend chamfer without another chamfer between the first outer-link endchamfer and the first additional outer-link end chamfer.
 9. Thebicycle-chain outer link plate according to claim 7, wherein the firstouter-link end chamfer includes a first radially outer edge and a firstradially inner edge, the first additional outer-link end chamferincludes a first additional radially outer edge and a first additionalradially inner edge, and the first radially inner edge is coincidentwith the first additional radially outer edge.
 10. The bicycle-chainouter link plate according to claim 9, wherein the first outer-link endportion has a fourth distance defined at the first radially outer edgeof the first outer-link end chamfer in the axial direction, and thefourth distance ranges from 0.79 mm to 0.83 mm.
 11. The bicycle-chainouter link plate according to claim 10, wherein the second distancecorresponds to the fourth distance.
 12. The bicycle-chain outer linkplate according to claim 1, further comprising an outline having anasymmetric shape relative to the first outer-link longitudinal axis whenviewed in the axial direction.
 13. The bicycle-chain outer link plateaccording to claim 1, wherein the second outer-link opening has anelongated shape extending along the first outer-link longitudinal axis.14. The bicycle-chain outer link plate according to claim 13, whereinthe second outer-link opening has a longitudinal axis, and thelongitudinal axis of the second outer-link opening is inclined relativeto the first outer-link longitudinal axis when viewed in the axialdirection.
 15. A bicycle chain comprising: the bicycle-chain outer linkplate according to claim 1; and a first link pin provided in the firstouter-link opening, the first link pin being engaged with the additionalouter link plate.